Thousands of people have been marooned as incessant rainfall for last few days coupled with onrush of hilly water triggered flooding in three districts of Sylhet division and some upazilas of Rangamati, Khagrachhari, Feni, Chittagong and Cox's Bazar.

A number of rivers in these districts are flowing above the danger level. Besides, flash flood damaged flood protection embankments, homesteads and crops, worsening the situation. The flood victims have been facing a shortage of dry food and pure drinking water.

Several thousands of people have taken shelter at different shelter centres set up by the government. Relief materials have been given to the flood-hit people.

Thousands of residents of 90 villages have been waterlogged in two upazilas of Moulvibazar and one upazila of Habiganj in Sylhet Division as the Khowai, Manu and Dhalai rivers swelled up. Floods also hit the Indian state of Assam, which usually has a ripple effect in this division.

The Manu was flowing 175 centimetres above the danger level at Manu Railway Bridge point in Kulaura upazila of Moulvibazar, said Shankar Chakraborty, executive engineer of Water Development Board's (WDB) local office. Also, the Dhalai was flowing 52 centimetres above the danger level at Dhalai Bridge point in Kamalganj, he added.

The water levels might rise further in the next 24 hours, he warned.

The onrush of hilly water damaged flood protection embankments in the districts worsening the flood situation. Thousands of people are facing a food and pure drinking water crisis.

A number of villages in Kamalganj and Kulaura upazilas have been inundated due to the swelling of the rivers.

Kamalganj Municipal Mayor Jewel Ahmed said five points of the Dhalai river protection dam collapsed, flooding around 30 villages and increasing the apprehension of damaging homesteads and crops.

Mohammad Mahmudul Huq, upazila nirbahi officer (UNO) of Kamalganj, said around 30 villages and 3,200 families have been affected by the flash flood and crops damaged on 700 hectares of land.

People wade through over knee-deep water in North Gonjapara of Khagrachhari yesterday morning. Photo: Collected/Saikat Dewan

The upazila administration of Kamalganj distributed rice among 125 flood-affected families in Karimpur and Munshibazar areas yesterday.

Several hundred volunteers have been working to protect dams on the Manu river at Miarpara and Khandakarer villages, said M Abdul Malik, chairman of Tilagaon Union Parishad.

Chairman of Sharifpur UP M Janab Ali said a 200-250-foot stretch of the flood protection embankment collapsed at Chatalghat village, making the bridge over the Manu vulnerable.

Chowdhury Mohammad Golam Rabbi, UNO of Kulaura, said around 60 villages and 2,500 families have been affected by flash flood in the upazila.

The upazila administration got 50 tonnes of rice from the DC office for the flood-affected families, he added.

All kinds of establishments in 60 villages in Kulaura, including schools, madrasas, mosques, temples, cropland and fish farms went under water, the UNO added.

The Khowai in Habiganj was flowing 180 centimetres above the danger mark in the town point, said Tauhidul Islam, executive engineer of WDB's Habiganj office.

The town protection dyke has been facing a threat of collapse in different points due to the increase in water level, he added.

The low-lying areas along the dyke have been inundated, he informed.

The upazila administration of Kamalganj has distributed rice among 125 flood-affected families in Karimpur and Munshibazar areas yesterday, said Mohammad Mahmudul Huq, UNO of Kamalganj.

In Sylhet, several villages of Rajaganj and Laksmiprashad Purbo unions and upazila sadar bazar of Kanaighat have been affected by flash flood yesterday afternoon.

According to WDB in Sylhet, the Surma was flowing at 13.7 metres yesterday afternoon which was 7.89 metres on Tuesday. It is around 145 centimetres above the danger level.

The Kushiyara was also overflowing 70 centimetres above the danger level at Amalshid point and 35 centimetres at Sheola point.

In Rangamati, several villages in Baghaichhari upazila have been submerged due to heavy rain, making thousands of people marooned.

Hundreds of families have already taken shelter at 20 shelter centres opened up by the upazila administration. Many schools have been flooded and road communication has been disconnected with other upazilas.

Around 300 ponds in the upazila have been flooded due to heavy rainfall and about 500 acres of land was submerged.

Baghaichhari UNO Muhammad Nadeem Sarwar said apart from rescuing the flood-hit people, they were also providing dry food and pure water.

Officials of different institutions and many voluntary organisations also took part in the rescue work.

Nuyen Khisa, medical officer of Baghaichhari Upazila Health Complex, said they formed eight medical teams for eight unions in the upazila for emergency treatment to the flood victims.

"We are ready for treatment. Our doctors and nurse are working at every union," he said.

In Khagrachhari, many areas in the Sadar are still under water.

The Changi river was flowing above the danger level due to heavy downpour in last two days.

Eight shelter centres have been opened for the flood-affected people where several hundred families have taken refuge.

In Cox's Bazar, around 20,000 people have been marooned in Garzonia and Kachchapia unions of Ramu upazila following heavy rain.

A three-year-old child drowned at Bomangkhil village in Garzonia. The villagers recovered the body later.

In Feni, 12 villages have been inundated by incessant rain in last three days with flash flood down from India devouring areas in Fulgazi and Parshuram upazilas, marooning inhabitants.

The onrush of water caused breach in the embankment of the Muhuri river at 10 points.

In many homesteads, people could not cook due to flood.

WDB Executive Engineer Md Kohinoorr Alam said the Muhuri was flowing 300 centimetres above the danger level.

In Chittagong, three upazilas were inundated due to incessant rainfall for last three days as of yesterday morning causing several thousand people marooned, reports UNB.

Severe flooding has been reported in Hathazari, Raozan and Fatikchhari upazilas that caused untold sufferings to the people.

In Hathazari, regional roads, fish enclosures, houses and business establishments were submerged by the rainwater.

Besides, embankments of the Halda river collapsed at different points, increasing the woes of the people. The Hathazari-Rangamati, Hathazari-Khagrachhari and Hathazari-Oxygen highways were inundated causing immense sufferings to the commuters, UNB reports.

The local administration has taken all-out preparations to tackle any kind of natural disasters, UNB says quoting Akterunnesa Sheuli, UNO of Hathazari.

The inhabitants of the low-lying areas have been asked to take shelter in local education institutions, she said.

[Mintu Deshwara, Dwoha Chowdhury, Anvil Chakma and Saikat Dewan contributed to this report]